/Engine/Source/Runtime/GeometryFramework/Public/Components/BaseDynamicMeshSceneProxy.h
Filter the triangles in aFMeshRenderBufferSetinto the SecondaryIndexBuffer. Requires that RenderBuffers->Triangles has been initialized.
void UpdateSecondaryTriangleBuffer ( [FMeshRenderBufferSet](API\Runtime\GeometryFramework\Components\FMeshRenderBufferSet) * RenderBuffers, const [FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) * Mesh, bool bDuplicate )